Lai P S, Chee S, Chiu L L, Sano K
Department of Paediatrics, National University of Singapore, Singapore.
Ann Acad Med Singap. 1997 Jul;26(4):415-20.
Neuroblastoma is a tumour derived from the sympathoadrenal progenitors of the neural crest. It is one of the most malignant solid tumours in childhood with an annual incidence of 9.4 per 10(6) children under 15 years of age. Recent studies suggest that immunocytological detection of neuroblastoma cells in bone marrow and circulating neuroblasts during treatment may predict clinical outcome and correlate with tumour relapse. The present methods of diagnosing metastasis in neuroblastoma include histological, biochemical and immunohistological analysis. Morphological distinction between tumour cells and primitive lymphoblasts in bone marrow is often difficult, and these methods may also not always be sensitive enough for early detection of the residual and minimally circulating tumor cells. A sensitive assay for detection of such residual cells using two tissue-specific markers, NFM and SYN, by reverse transcriptase-polymerase chain reaction (RT-PCR) is reported here. Analysis of the specificity of this assay in three neuroblastoma cell lines, namely IMR 32, SK-N-SH and SY5Y showed positive expression while control peripheral blood mononuclear cells (HL 60) were negative. In reconstituted cell spiking tests, this method has the ability to detect 1-10(3) neuroblastoma cell in 10(7) normal peripheral blood mononuclear cells (PBMC), as shown by serial dilution and limiting dilution. The NFM marker was found to be a more sensitive marker. The specificity and sensitivity of this technique makes it suitable for future application in detection of minimally disseminated tumour cells in neuroblastoma patients.
神经母细胞瘤是一种起源于神经嵴交感肾上腺祖细胞的肿瘤。它是儿童期最恶性的实体肿瘤之一，15岁以下儿童的年发病率为每10⁶人中有9.4例。最近的研究表明，在治疗期间对骨髓中的神经母细胞瘤细胞和循环神经母细胞进行免疫细胞检测可能预测临床结果，并与肿瘤复发相关。目前诊断神经母细胞瘤转移的方法包括组织学、生化和免疫组织学分析。骨髓中肿瘤细胞与原始淋巴细胞的形态学区分往往很困难，而且这些方法对残留和微量循环肿瘤细胞的早期检测可能也不够敏感。本文报道了一种通过逆转录聚合酶链反应（RT-PCR）使用两种组织特异性标志物NFM和SYN检测此类残留细胞的灵敏检测方法。对三种神经母细胞瘤细胞系，即IMR 32、SK-N-SH和SY5Y的该检测方法的特异性分析显示为阳性表达，而对照外周血单个核细胞（HL 60）为阴性。在重组细胞加标试验中，如系列稀释和有限稀释所示，该方法能够在10⁷个正常外周血单个核细胞（PBMC）中检测到1-10³个神经母细胞瘤细胞。发现NFM标志物是更灵敏的标志物。该技术的特异性和灵敏性使其适用于未来检测神经母细胞瘤患者中微量播散肿瘤细胞。
